Re: RAID + PostgreSQL?

MG wrote:
> Hello,
>
> we are using PostgreSQL 8.0.3 together with RAID on OpenServer 6.
>
> When we do a big SELECT-query the whole maschine becomes very very
> very slowly or stands.
> The maschine has 3 GB RAM, so we suppose it`s the RAID.
>
> Has anyone some experience with RAID + PostgreSQL?
>
> Where does PostgreSQL saves his temporary files? Perhaps these are the
> reason for the bad performance.
>
> Greetings
>
> Michaela
What kind of RAID? I know if you have it set up to mirror it becomes
slow as pond water.
I have a server that was a hand me down so I did not have a choice in
the RAID and it was set up to mirror with two drives and
the performance on large selects was very bad. The performance would
increase by 50 or more percent if
fsync = off is set in the postgresql.conf file.

Do a search of the mailing list archives, there is a lot of talk about
RAID and battery backed write caches etc.

--
Tony Caduto
AM Software Design
http://www.amsoftwaredesign.com
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